Observation of rotational revivals for iodine molecules in helium droplets using a near-adiabatic laser pulse

Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaperJournal articleResearchpeer-review

© 2018 American Physical Society. A 160-ps near-Gaussian, linearly polarized laser pulse is used to align iodine (I2) molecules embedded in helium nanodroplets. The rise time of the laser pulse is sufficiently long and smooth that the alignment, characterized by (cos2θ2D), behaves adiabatically during the pulse turnon. However, after the laser pulse has turned off (cos2θ2D) stays above 0.50 and a recurrence structure occurs ∼650 ps later. Measurements on isolated (I2) molecules with identical laser pulses are used to identify, through analysis of the observed half- and full-rotational revivals, that the nonadiabatic postpulse alignment dynamics results from a mild truncation of the trailing edge of the laser pulse. This truncation establishes a well-defined starting time for coherent rotation, which leads to the revival structures observed both for isolated molecules and molecules in He droplets. In the latter case the time-dependent (cos2θ2D) trace recorded here is compared to that obtained previously for a 450-fs alignment pulse. It is found that the observed revivals are very similar.
Original languageEnglish
Article number013427
JournalPhysical Review A
Publication statusPublished - 30 Jan 2018

See relations at Aarhus University Citationformats

ID: 122942366